亲权鉴定若干问题综述

对亲权鉴定中遗传标记的研究历史及现状进行了综述，并对国际法医遗传学会亲子鉴定委员会关于DNA生物计算的建议进行了解读。     

Prenatal and newborn paternity testing with DNA analysis

In rape against youthful girls which yields pregnancy after the abortion DNA examinations can be performed from the aborted foetal material to provide evidence of paternity of the suspect. In our present work we demonstrate six cases: four of them are rape cases and two where the mother abandoned her newborn baby. These cases proved that DNA-STR profiles can be determined from foetus after the abortion and perpetrator of a rape can be found. Due to our result we suggest that not only placenta but also bloody vernix caseosa is useful tissue for identifying the putative mother because vernix caseosa can be the carrier of the mother's blood.     

CODIS位点在排除亲权中的应用价值

目的 对 CODIS位点 (FGA、 vWA、 CSF1PO、 TH01、 TPOX、 D3S1358、 D5S818、 D7S820、 D8S1179、 D13S317、 D16S539、 D18S51和 D21S11共 13个 STR位点 )在 100例排除亲权的亲子鉴定中的应用价值进行研究。方法 采用 Profiler Plus及 Cofiler荧光标记复合扩增系统,通过 310遗传分析仪对上述二个检测体系扩增产物的基因型进行分析。结果 在排除亲权的母亲－孩子－假设父亲三联体组中,所有观察案例其出现的排除指标数都在 3个以上,平均排除指标数为 6.63个;在假设父亲－孩子二联体组中, 94.0％的观察案例其排除指标数均在 3个以上,平均排除指标数为 5.01个。结论 CODIS位点在排除亲权的二联体和三联体组合亲子鉴定中,都符合鉴定应用要求 ;选择多态性较高的位点与增加排除指标存在直接的联系,以 DP、 H、 PE作为衡量 DNA位点应用价值的指标在具体鉴定实践中是可靠和可行的。     

Genetic analysis of erythrocyte uridine monophosphate kinase and aminolevulinate dehydrase and its application to paternity testing

Simultaneous determination of uridine monophosphate kinase (UMPK) and aminolevulinate dehydrase (ALAD) has been carried out after discontinuous starch gel electrophoresis in the Galician population (NW Spain), including 129 families with a total of 291 descendents. Formal genetic studies are in agreement with the autosomal codominant way of inheritance for each locus. No evidence of phenotype association between both loci among the offspring is observed. Chance of exclusion for non-fathers is 0.041 13 for UMPK and 0.0702 for ALAD configuring a total exclusion rate of 0.1085 when both systems are evaluated together.     

Deduction of paternity index from DNA mixture

Determination of individual genotypes in DNA mixture remains a challenge in forensic science. Using an approach of mixture of distributions, this article provides formula for calculation of paternity index (PI) in cases where only tissue mixture of the mother and alleged father, the genotypes of the mother and child, but not that of the alleged father are available. The formula has been used to solve a real case using mother's vaginal tissue contaminated with semen from alleged father.     

Computer analysis of parentage in relation to maternity and paternity

General formulas for statistical calculations of parentage by means of blood group analysis are presented in relation to those of maternity and paternity. Based on these formulas, a computer program has been devised to calculate plausibilities, exclusion probabilities, and distributions of log (Y/X) of parentage for any blood groups. The program also gives numerical values of these quantities of maternity and paternity. The values of plausibility and exclusion probability are highest for parentage, and decrease in the order of paternity and maternity. Concerning the distribution of log (Y/X) for true families, a simple relation holds for the ratio of the mean value of log (Y/X) in parentage ap, to that in paternity af, and to that in maternity am as, ap: af: am = 1: 0.6: (0.6)2 This relation holds for all 14 blood groups examined.     

Use of DNA polymorphism in forensic paternity evaluation

Problematical paternity cases were additionally subjected to DNA-polymorphism analysis. 5 cases are reported, focusing on problems due to, 'silent' allele transmittance, relatively low probability for paternity, obvious occurrence of the extremely rare Rh gene complex CWc, involvement of brothers as putative fathers, non-paternity of a man although his W-value was 99.975%. The aim of this paper is to demonstrate the need for DNA-polymorphism analysis, if conventional blood group tests do not lead to a clear-cut decision. Extended typing of conventional blood group polymorphisms (except HLA) cannot compete with highly polymorphic DNA loci.     

DNA profile evidence in complex disputed paternity cases: The analysis of 300 real cases

In disputed paternity cases where the putative father is unavailable DNA from one or more of his relatives could be used. However, interpreting results is often difficult, because of the partial information regarding the parental genotype obtained from his relatives. We analyzed results obtained in 300 real paternity cases performed through close relatives of the real father (sib, half-sibs, one grandparent and/or uncle). DNA was typed with PowerPlex (Promega) and the LR estimated with the Software BDGen. As expected the higher LR values were achieved with sibs and half-sibs (in such cases where his/her mother was available for testing). The LR values were tight related to the number of uninformative loci, which varied between 0 and 13. In 10% of the reviewed cases, 10 or more non-informative loci were observed; all of them associated LR values below 0.01. Thus, providing evidence in favor of no relatedness.     

亲子关系诉讼中的亲子鉴定推定及其改革

最高人民法院于2011年创制的亲子鉴定推定以实现亲子确认诉讼的确定性解决为目标,主要的缺陷是模糊了举证证明责任制度的程序地位、与举证证明责任的程序功能相悖、适用条件模糊。作为其理论依据的证明妨碍理论难以为亲子鉴定推定提供正当性,事实上域外很少有采用亲子鉴定推定的立法,即使个别采亲子鉴定推定立法例的国家,司法中对之的适用也非常谨慎。应对亲子确认诉讼中,当事人一方拒绝配合协助鉴定的情况,可以坚持直接强制为原则,并辅之鉴定材料的替代获取。     

二联体亲权鉴定风险分析

目的探讨二联体亲权鉴定时存在的风险。方法选取22组经Goldeneye~(TM) 20A试剂盒检测后只有一个或没有不符合基因座的无关个体对构建假想家系。对其增加检测STRtyper-10G和/或AGCU 21+1 STR系统直至所有组不符合基因座个数大于3个,累积父权指数(CPI)不大于0.000 1。以三种规则:(1)不符合基因座数大于3个;(2)CPI值小于0.000 1;(3)同时满足(1)和(2),作为排除依据,使用不同数量的基因座(19个、26个、39个和46个)进行检测,讨论无关个体对的排除情况是否存在差异。结果 22组无关个体对,使用19个基因座和39个基因座以上的检测系统达到排除结果的分别为0组和22组。结论二联体亲子鉴定,使用19个基因座进行检测仍存在结果错判,39个基因座以上的检测系统能更有效的避免二联体的鉴定风险。     

上海地区D1S80位点基因频率分布及其在亲子鉴定中的应用

目的：将D1S80位点的DNA多态性分析应用于亲子鉴定。方法;PCR、聚丙烯酰胺凝胶电泳及溴已锭染色。结果：获得D1S80位点的DNA多态性分布数据。结论：D1S80位点的PCR检测方法可成功地用于亲权纠纷案的鉴定。     

Isolation of the DNA minisatellite probe MZ 1.3 and its application to DNA 'fingerprinting' analysis

A minisatellite probe, MZ 1.3, detecting hypervariable fragment patterns was isolated from a human genomic library. A repetitive sequence of 27 bp length was identified which is contained in the probe approx. 40 times. The MZ 1.3 repeat shows variable homology of 53-73% to the repetitive sequence of the protein III gene of the bacteriophage M13 genome. Polymorphic restriction fragment patterns were found with MZ 1.3 using the enzymes Hinf I, BstN I, Hae III, Mbo I, PstI/Pvu II, and Rsa I. An average of 18 polymorphic fragments was observed using Hinf I as enzyme. The band sharing frequency after Hinf I digestion among unrelated individuals was determined to be 23.8 +/- 7.2%. An example for the application of MZ 1.3 to paternity testing in an incest case is given. The probe can be used with radioactive or non-radioactive detection systems. An approach is presented to compare polymorphic fragment patterns from individuals obtained by independent gel runs on the basis of relative band positions (RBP) and calculated in a computerized analysis.     

低拷贝模板DNA分析技术研究进展

近年来,低拷贝（LCN）模板类生物物证在法医DNA分析中占有了越来越重要的地位。用于低拷贝模板DNA的检测方法也得到飞速发展。本文通过对各种LCN-DNA分析技术如增加扩增循环数、纯化扩增产物、全基因组扩增、激光捕获显微切割等检测方法的综述,以及对LCN—DNA检测结果的分析评价,全面介绍LCN分析技术在法庭科学应用的最新进展及存在问题。最大限度地拓展低拷贝模板类生物物证在刑事司法领域的应用。     

The decision theory of paternity disputes: optimization considerations applied to multilocus DNA fingerprinting.

The solution of paternity disputes using results from scientific analyses is studied from a decision-theoretical viewpoint. Two alternative approaches to decision making, the so-called 'Bayes' and 'Minimax' strategies, are described and discussed. If prior probabilities of paternity are exactly known, then Bayes decisions are (a) independent of the source of evidence and (b) optimal with respect to average losses caused by wrong decisions. However, it is concluded that Minimax decisions, which depend upon the employed test system but not upon prior probabilities, are more appropriate in paternity cases if equal prior good will towards disclaimed children and alleged fathers is demanded. It is further demonstrated that, when major evidence about paternity comes from multilocus DNA fingerprinting, prior probabilities must be known quite accurately for Bayes decisions to be superior with respect to average losses. Finally, we are able to show that 'quasi' Bayes decision making, that is, adopting a neutral prior probability of 0.5 but leaving thresholds for decision making unchanged, coincides with Minimax decision making if multilocus DNA fingerprinting is employed.     

Validation issues around DNA typing of low level DNA

A recent ruling in the Crown Court of Northern Ireland, R v. Hoey, [R v Sean Hoey. 2007, Crown Court of Northern Ireland] has raised questions about the validity of one variant of DNA analysis, often termed LCN. The ruling and subsequent discussion also raises questions about what constitutes validation of a technique.This paper examines what can be achieved in a laboratory based validation study against the Daubert standard and against guidance given in the UK. There is a significant discrepancy between what can be achieved and the Daubert standard but much less of a discrepancy against the UK guidance. Much of the difference relates to differences in word usage, definitional difficulties, and a lack of mutual understanding and communication between the judiciary and forensic scientists. This highlights a gap that needs attention.